When a standard curve whose x-axis is this quantity is not hyperbolic, Furchgott's method may be used. The base-10 logarithm of a ratio of two values of this quantity appears in the Gaddum equation, which is used to generate Schild plots. In some calculations, this quantity is multiplied by one fraction called the “salt factor” and another fraction denoted capital F. “Loading” values of this quantity are proportional to the volume of distribution, while “maintenance” values are proportional to the (15[1])(*) clearance. Curves that correlate this quantity with a “response” can measure the “median effective” value of this quantity, which is large (10[1])when bioavailability is poor. The value of this quantity that kills (-5[1])50% of subjects is denoted (10[1])LD50. Paracelsus said that “the poison” is “made by”, for 10 points, what amount of a drug given to an organism? (10[1])■END■